1. Field of the Invention
The present invention relates to a composite member for a vehicle body, in particular, a vehicle roof, comprising a fiber-free outer skin and a fiber-reinforced support layer which is provided at the inner side of the outer skin for reinforcing the outer skin as well as to corresponding method for manufacturing.
2. Description of Related Art
A composite member according to the preamble is known, e.g., from German Patent DE 102 02 911 C1, where, in the region of the interface between the outer skin and the support layer, an interface layer is provided in the support layer in which the fiber concentration is increased in comparison to the region outside the interface layer of the support layer in order to provide a composite member with a higher temperature stability. The support layer is made of polyurethane which is reinforced by means of a long fiber injection, while the interface layer is made of polyurethane reinforced by means of long fiber injection or is established by inlaying an additional glass fiber mat.
Additional composite members which form a roof module for a vehicle and which are provided with a fiber reinforced support layer of polyurethane with a homogeneous distribution of fibers are known, e.g., from German Patent Application DE 102 05 295 A1 (which corresponds to U.S. Patent Application Publication 2003/0152748 A1), German Patent Application DE 102 07 295 A1, U.S. Pat. No. 6,378,208 B1 as well as European Patent Application EP 0 995 667 A1 and European Patent Application EP 1 384 655 A2 (which corresponds to U.S. Pat. No. 6,860,548 B2). In the latter two documents, the reinforcement of a polyurethane layer by means of inlaying of a tissue or woven and non-woven fabrics is mentioned as reinforcement.
A disadvantage of these composite members is that, for achieving a sufficient stability of the support layer, the needed fiber concentration leads to a non-uniform surface of the outer skin, especially after a thermal load.